The rest of October and Halloween outlook

The early portion of October produced some very warm weather across the Inland Northwest before showers and cooler temperatures arrived early last week. Despite the showers Oct. 10 and 11, plus the expected rainfall early this week, moisture totals across the Inland Northwest are below normal once again for October.

At Cliff’s station, as of late Sunday, only 0.22 inches of rain has fallen for the month. The normal precipitation for Coeur d’Alene for October is 2.22 inches. It’s been drier at the Spokane International Airport as a puny .08 inches has fallen through the first half of October.

Once the storms pass through our region by the middle of the week, a strong ridge of high pressure is expected to rebuild across the western U.S. The high is forecast to be strong enough to keep any major storms out of our area until at least the end of the month when we get close or enter the full moon cycle Oct. 28. However, we could see a few showers from a weak storm system this weekend. Unless the end-of-the-month rainfall is significant, we’ll likely have the second month in a row with below-normal precipitation in Coeur d’Alene and the rest of the Inland Northwest. Over the last several months, the full moon cycles have been strong enough to produce some impressive rainfall totals, so we’ll have to wait and see how this one develops.

Temperatures will continue to be mild into next week. The long-range computer models are indicating the possibility of readings dropping to the freezing mark early next week into the lower elevations. That particular cold air mass is expected to be mostly to our east, but the higher elevations as well as the mountain regions would have a better chance of freezing temperatures. If the lower elevations do not drop down into the lower 30s next week, then it looks like we’ll likely experience those frigid temperatures in November. It’s also possible that we’ll see some snowfall in the higher elevations at the end of this month as well.

During that full moon cycle, there’s also a chance we could see some rainfall around Halloween. Based on records going back to 1895, moisture has fallen on Halloween a little over 40% of the time in the Coeur d’Alene region. The average temperatures on Halloween range from a high of 52 degrees and a low of 34 degrees. The warmest Halloween in Coeur d’Alene occurred in 1938 with a pleasant 72 degrees. Three years earlier, in 1935, it was the coldest with a low of only 2 degrees. The wettest Oct. 31 in recorded history occurred back in 2016 as 1.20 inches of rain was measured. In terms of snowfall, Coeur d’Alene did receive 3 inches on Halloween in 1971.

Last year, a storm system dropped 0.14 inches of rain. The next day, Nov. 1, a hefty 0.81 inches of rain fell in the lower elevations with snow reported in the higher mountains. Temperatures went from a high of 56 degrees Oct. 31, 2022, to a chilly 44 degrees Nov. 1.

However, despite the drier-than-normal weather over the last several months, some of the fall foliage around the region has been glorious. Some readers have sent me pictures and I’ve noticed many great photos on social media. Weather conditions have also been very favorable for the great color and harvesting of the region’s apple crops.

As I’ve been mentioning in other articles, sea-surface temperatures along the equatorial regions continue to climb, indicating that we have an El Niño in the south-central Pacific Ocean. According to the Climate Prediction Center, forecasters are favoring at least a “strong” El Niño into the early portion of 2024. Forecasters also say there is an 80% probability that El Niño will likely last through the next spring season. There is also about a 30% chance this event will be “historically strong” and could challenge the super-strong El Niños in 2015-16 and 1997-98.

During the 2015-16 season, Coeur d’Alene and surrounding regions had a wet late fall and winter season after a drier-than-normal September and October. For the snowfall season, we had a below-normal 56.2 inches, but 1.9 inches did fall on Christmas Day in Coeur d’Alene in 2015.

Although the chances of a White Christmas are lower during El Niño years, there have been instances when we’ve seen measurable snowfall, and 2015 is a good example. Right now, based on current trends, we’re going to put the odds at slightly less than 50/50. Stay tuned.

In terms of the winter forecast for the 2023-24 season, there are government and private entities that have a difference of opinion. I’ll feature some of those outlooks next week.

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Contact Randy Mann at randy@longrangeweather.com.